By: Roche, Kathleen M., Mekos, Debra, Alexander, Cheryl S., Astone, Nan Marie, Bandeen-Roche, Karen, and Margaret E. Ensming
Studying data from the National Longitudinal Study of Adolescent Health, these researchers find that only 9% of adolescent virgins from two-biological-parent families initiated sexual intercourse 11 months after an initial interview relative to 16% and 21% of adolescent virgins from stepparent families and single-parent families, respectively. Furthermore, they find that living with two biological parents decreases the odds of initiating sexual intercourse by 45% relative to living with a single parent.
Parenting influences on early sex initiation among adolescents: How neighborhood matters. Journal of Family Issues 26 (1): 32-54.